A relatively small leak in a mechanical system can cause tremendous damage when not discovered quickly. Claims of this nature seem to go hand in hand with a second or vacation home, homes under construction (builders risk) or when the insured is away for an extended period. During a mechanical failure, water flowing at a rate of 8 to 16 ounces per minute can result in a discharge of 90 to 180 gallons per day, or over 1,000 gallons a week.

Background

Several hundred gallons of water have leaked from an attic-mounted humidifier and flowed down the walls, buckling the hardwood floors and damaging some antique furnishings. After a hurried call to a restoration company, questions like, "What went wrong" need to be answered. After all, the house had been designed by the best architect and built by qualified craftsmen, and had a part-time house manager to check on things and tend to maintenance problems.

Workers were rapidly drying the place out and getting bids for the $100,000 in repairs, when the finger pointing began. At this point, a qualified professional engineer is contacted to objectively examine the evidence and determine the cause.

Findings

1. There were no leaks in the supply line or the unit control valve.
2. The evaporative panel in the humidifier was clogged with fluffy mineral residue and had deteriorated to the point where the corners were missing and the surface crumbled when touched.
3. An invoice showed the panel had been replaced fourteen months ago.
4. The service manual stated that the panels should be replaced annually, and the manufacturer's website "Frequently Asked Questions" (FAQ) stated, "For the best performance we recommend the water panel be replaced once a year, either prior to the start of or at the end of the heating season."
5. The owner stated he had told the manager to replace the panel in the spring, but spring entails 3 months and the manager had purchased it, but it was in the trunk of his car.
6. No service log or tag showing last and next due service dates was provided, but the maintenance instructions were available in a three-ring binder.
7. The security log indicated the house had not been entered in five days.
8. The service manual states that the saddle valve should not be used to regulate the water flow but should be in the fully open position to flush trouble-causing minerals down the drain. Because this valve was closed it is not known if it was in the fully open position during operation.
9. The "FAQ" section of the website stated, "The unit offers total flexibility in the installation of our humidifiers in that they will operate properly with either hard or soft water. Connecting to hard water will leave mineral deposits on the water panels that are scaly and hard in nature. Connecting to soft water may leave mineral deposits that are fluffier in nature. The bottom line is the water panel will typically last a full heating season using either type of water."
10. No secondary water containment such as a drip pan was designed into the humidifier nor did the architect or installing contractor add one.
11. There was no water source to properly carry out the maintenance instruction, "Then flush it with water under pressure and slip it back onto the black drain fitting."

Conclusions

1. The cause of the leak was the overflow of the supply water that occurred when the drain was plugged by the fluffy residue.
2. Although the exact amount of water flow could not be determined a flow as small as one cup per minute would yield 450 gallons in five days.
3. In hindsight, if a strict twelve-month interval for panel replacement had been followed the leak would have been avoided, however the manufacturers literature does not require that level of rigor.
4. Annual replacement may not be frequent enough considering the water chemistry and frequency of use. In that the blockage occurred only fourteen months after replacement, the heating season interval allows little safety factor for the large variation in operating conditions.
5. The humidifier design is not robust in that it does not provide a backup drain channel when the one hole is plugged. Given enough time the humidifier panels, by design, will always fail and quite likely plug the drain. Relying on the preventive maintenance schedule as the only protection against catastrophic overflow is not sound engineering.
6. The original house design does not accommodate the maintenance requirements, as there is no convenient source of pressurized water.
7. Prudent home design and humidifier installation would have provided a secondary drain system, in particular in a house that is not continuously occupied.

Could this loss have been avoided?

As you can see by the facts of this scenario, many factors played a role but, safeguards can be put into place that could quite possibly reduce the extent of the damage sustained.

1. Installing secondary drain pans. These can be as simple as plastic or metal basins that drain to the existing drain lines. Electronic "wet floor alarms," that give early warning but do not prevent overflows, might be considered as an enhancement to the drain system.
2. Installation of hose bibs in the supply lines to accommodate the proper flushing of the lines.
3. Establishing a maintenance schedule with some form of "tickler" system for specified service dates, and reducing the time between panel services if early blockage is occurring.
4. Ensuring that the individual responsible for changing the panels has the requisite skill and tools for the tasks.

Armed with factual information you can now move into the knotty issue of financial responsibility-subrogation can be fun!!!

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